combobox type ahead with 'any' match

I am new to ext-js and is it possible to have a type assist in combobox which filters the list with items that has the user typed in characters . For example in the "States" combobox if the user types in "Carolina" the list needs to populate "North Carolina" and "South Carolina". Any help is greately appreciated.

hopefully the 3.0 release would have this option it would be more easy to use than overwrite the combo, maybe with a property like (anymatch:bolean), also thanks for the overwriting code it help me a lot but you need to set typeAhead: false or simply don´t put it so it works fine , thanks "vraj"